In law, cross-examination is the interrogation of a witness called by one's opponent. It is preceded by direct examination (in the United Kingdom, Scotland, Australia, Canada, India and Pakistan known as examination-in-chief) and may be followed by a redirect (re-examination in England, Scotland, Australia, Canada, India, Hong Kong and Pakistan).
In the United States federal courts, a cross-examining attorney is typically not permitted to ask questions which do not pertain to the testimony offered during direct examination, but most state courts do permit a lawyer to cross-examine a witness on matters not raised during direct examination. Similarly, courts in England, Australia, and Canada allow a cross-examiner to exceed the scope of direct examination.
Since a witness called by the opposing party is presumed to be hostile, cross-examination does permit leading questions. A witness called by the direct examiner, on the other hand, may only be treated as hostile by that examiner after being permitted to do so by the judge, at the request of that examiner and as a result of the witness being openly antagonistic and/or prejudiced against the opposing party. 
The main purposes of cross-examination are to elicit favorable facts from the witness, or to impeach the credibility of the testifying witness to lessen the weight of unfavorable testimony. Cross-examination frequently produces critical evidence in trials, especially if a witness contradicts previous testimony. The advocate Edward Marshall-Hall built his career on cross-examination which often involved histrionic outbursts designed to sway jurors. Most experienced and skilled cross-examiners however, refrain from caustic or abrasive cross-examination so as to avoid alienating jurors. John Mortimer, Queen's Counsel, observed that "cross-examination" was not the art of examining crossly. Indeed the good cross-examiner gets a witness to assert to a series of linked propositions culminating in one that undermines that witnesses' evidence rather than pursuing an antagonistic approach.
Cross-examination is considered an essential component of a jury trial due to the impact it has on the opinions of the judge and jury. Few lawyers practice trial law or complex litigation and typically refer such cases to those who have the time, resources and experience to handle a complex trial and the commitment involved to complete a trial successfully. Few attorney's get the practice neccessary to develop the techniques needed to do an effective job cross-examining a witness. It is sometimes referred to as an art form, due to the need for an attorney to know precisely how to elicit the testimony from the opposing witness that will help, not hinder their client's case. Typically a cross-examiner must not only be effective at getting the witness to reveal the truth, but to in most cases reveal confusion as to the facts such as time, dates, people, places, wording etc. More often than not a cross-examiner will also attempt to undermine the credibility of a witness if he will not be perceived to be a bull (such as discrediting a very elderly person or young child). The cross-examiner often needs to discredit a potentially bias or damaging witness in the eyes of the jury without appearing to be doing so in an unfair way. Typically the cross-examiner must appear friendly, talk softly and sincerely to relax the guarded witness. They typically begin repeating similar basic questions in a variety of different ways to get different responses which will then be used against the witness as misstatements of fact later when the attorney wants to make their point. If it is too obvious the questions are too clearly repetative and making the witness nervous, the other attorney may accuse the cross examiner of badgering the witness. There is a fine line between badgering and gettting the witness to restate facts differently that is typically pursued. The less the witness says, and the slower the witness speaks, the more control they can maintain under the pressure of a crafty opponent. The key for a witness is to understand the facts that they believe to be the case and not add additional thoughts to those facts, less they be used to undermine the actual facts. Sticking to the brief known facts is key for the witness, making it difficult for the cross-examiner to make the witness appear confused, bias or deceitful. The cross examiner will assume the witness has been told that and begin asking supporting questions about where the witnesss was, what time it was, what the witness saw, what they said.. and sooner or later upon asking again the witness may use a different word that will give the cross-examiner a chance to ask the question again doubtfully and pointedly implying contradiction. The witness will try typically to explain and clarify which sometimes reveals weakness in the witnesses statements of fact. Other times the witness is just being being truthful but undermined for the purpose of casting doubt to the jury and or judge.
Full article ▸